From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A5842C43387 for ; Sat, 12 Jan 2019 17:20:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7C9672084E for ; Sat, 12 Jan 2019 17:20:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726426AbfALRUH (ORCPT ); Sat, 12 Jan 2019 12:20:07 -0500 Received: from mout.gmx.net ([212.227.15.18]:43379 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725920AbfALRUH (ORCPT ); Sat, 12 Jan 2019 12:20:07 -0500 Received: from longitude ([109.90.232.48]) by mail.gmx.com (mrgmx002 [212.227.17.190]) with ESMTPSA (Nemesis) id 0MPUlV-1geGGm3i65-004iaL; Sat, 12 Jan 2019 18:14:42 +0100 From: =?UTF-8?q?Jonathan=20Neusch=C3=A4fer?= To: linux-kernel@vger.kernel.org Cc: =?UTF-8?q?Jonathan=20Neusch=C3=A4fer?= , Linus Torvalds , Andrew Morton , Dominik Brodowski , Thomas Gleixner , Cyrill Gorcunov , "Gustavo A. R. Silva" , Yang Shi , Kristina Martsenko , Jann Horn , Kees Cook Subject: [PATCH v2] kernel/sys.c: Clarify that UNAME26 does not generate unique versions anymore Date: Sat, 12 Jan 2019 18:14:30 +0100 Message-Id: <20190112171432.11309-1-j.neuschaefer@gmx.net> X-Mailer: git-send-email 2.20.1 In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Provags-ID: V03:K1:X7YqSsUp/bUlVd/W068eqfOmXqKb06eaYslFsm0tTXnattKabUe LuLVGZmaBU1aPjsTCpbN5fICrSKCMHqElBJyvT0hr3kSSbiclPE/pVYONjd1eXveUe76JjJ 842UiD/x1a2gcsbz4tWVlcbsJ4uSF4v/s79c5mBfhGqfACCdQ3vrdl/ROXK6ih7UeTEcYWE bNR6cZD/bZ6TbSAb0otUA== X-UI-Out-Filterresults: notjunk:1;V03:K0:8iGpCx1FRhk=:3gP/qYWWrHPjn0zzBSBKpG 35fPm+OgWIk/NDD3q2b5lSxTNwB5xh3Q2c9ZDlo/KprfsZN5oi+6Xd3S2u9CIM4YofdpTezKr VtxxzfRGN5JOVAO7blaKB7G1eLF5LrCuA3txtpqLMe+90pxM0T5H5I6RZCfD5PslvRFLUlphW jMRs9WnR0kGG/p5w6SVp0Pyp8nYf0BTQP4PQieyckVKfxh3YdcfLyaY+TsNhJnd5Lyi1DqWv4 DJZbuyFH1f+SqP+YOW1Q42OZt7O/YLf2zRABQznmtkwGJgW1RUGoRR1izVFKghPzHAADB+VKD eqMUbcj9TrLXGlapLfhJkN0F9ota7PmK/ggTUt916yviBSDk+QRuqOuIV4T0TItC+GhEgWDdS awyKbh+06CYAHgjRfcZnpLbowggGlm2iyhsEXBwPrJnzbjlp1vNf/4yAiaeV6HkE7iK8f/HbR umFenz/3EO9pC3sx5DhVaJSGIu8c4ixk52+HZTYDAQ+nm6bgSYfmB4mkm7cp3otjeYl0qhHm/ tfzXqHfJ1crfSwkta9Jb/aVj2O17l7hQ2BXcNKYJZqXQxxESmlyRjjJ3O3DCoK1kXCswAzxgd Hr2AhAy0vstellQxgp3zwbyZIGecNxjyNa2gPt1TLIMhI4g6uYG1X3dR7h0/r1sUQ72KhHrLk YGRmHmIMC37mAWK3Ru3o1++/hII6Vibm9uo2sM9c3ju713fOUgQqaScW//j3/WF7LgFcIkqhP zdkQ4J4L0RanQSMFypWsGzZ7U/qoWeKrhIMjUTexWjgd8HJOwIFaPQ2EtRRre9q+BZDBq6eeU a7xSEOxm9qBDocU0uvOxlbcxf9AiPPyiB7UHejEixL5PB9BdKvX9SLxtpJCpw5SEzIteg1yqe xcTsHPPUhQJzwaOsrBuQpxABlOBu3pGZJXnSSH9NwNFmSZ0ySqq3D0sqgjGHWyfk1dM4mfebN XO9lxGkjWag== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org UNAME26 is a mechanism to report Linux's version as 2.6.x, for compatibility with old/broken software. Due to the way it is implemented, it would have to be updated after 5.0, to keep the resulting versions unique. Linus Torvalds argued: > Do we actually need this? > > I'd rather let it bitrot, and just let it return random versions. It > will just start again at 2.4.60, won't it? > > Anybody who uses UNAME26 for a 5.x kernel might as well think it's > still 4.x. The user space is so old that it can't possibly care about > differences between 4.x and 5.x, can it? > > The only thing that matters is that it shows "2.4.", > which it will do regardless. Cc: Linus Torvalds Signed-off-by: Jonathan Neuschäfer --- v2: - Switched to documenting why UNAME26 is not updated v1: - https://lore.kernel.org/patchwork/patch/1029578/ --- kernel/sys.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/sys.c b/kernel/sys.c index a48cbf1414b8..f7eb62eceb24 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1207,7 +1207,8 @@ DECLARE_RWSEM(uts_sem); /* * Work around broken programs that cannot handle "Linux 3.0". * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40 - * And we map 4.x to 2.6.60+x, so 4.0 would be 2.6.60. + * And we map 4.x and later versions to 2.6.60+x, so 4.0/5.0/6.0/... would be + * 2.6.60. */ static int override_release(char __user *release, size_t len) { -- 2.20.1